1. Field of the Invention
The present invention relates to a flexible flat cable, and more particularly, to a flexible flat cable in which a plurality of conductive wires are disposed between an upper film and a lower film, and an air gap is formed between the conductive wires.
2. Description of the Related Art
“Flat cable covering and flat cable using same” is disclosed in Korean Patent No. 10-0841000 (registered on Jun. 18, 2008).
Referring to the flat cable covering and the flat cable using the same, the flat cable covering is prepared by sequentially laminating on one surface of a heat-resistant substrate film with an adhesivity-improving layer and a flame-retardant heat-adhesive resin layer including 20 wt % to 40 wt % of a heat-adhesive resin mainly including a linear saturated polyester-based resin and 80 wt % to 60 wt % of filler constituents mainly including a mixed flame retardant including at least a hydrated metallic compound, antimony oxide, and a nitrogen-based compound. In addition, the flat cable is manufactured by stacking the covering on both sides of a plurality of conductors arranged in parallel in such a manner that the flame-retardant heat-adhesive resin layers make contact with the both sides of conductors, and heating and pressurizing the covering for integration.
However, since the flat cable covering and the flat cable using the same completely surround a periphery of the conductors by the flame-retardant heat-adhesive resin layers, there is a disadvantage that great transmission data loss (decrease in a transmission data rate) is caused due to a dielectric constant of the flame-retardant heat-adhesive resin layers.